Injuries to muscles include acute injuries to skeletal muscles such as contusions (bruises), lacerations, ischemia, strains, and complete ruptures. These injuries may cause tremendous pain and can incapacitate the affected person, preventing them from being able to go to work or even to participate in normal daily activities.
Skeletal muscles can become injured for a variety of reasons including over-use, trauma, infections and loss of blood circulation. In general, muscles have adequate repair capacity particularly in young people, but this repair process can become ineffective in older people or after repeated rounds of over-use, severe trauma or other processes. In such cases, the muscles lose function and strength of contraction and can be replaced by scar tissue (connective tissue) that by lacking contractility, causes loss of muscle function. Current therapies include massage, ultrasound, hyperbaric oxygen delivery, and drug treatments such as fenoterol and insulin-like growth factor-1. These therapies can provide some beneficial outcomes, but are far from ideal in terms of effectiveness and efficiency. In addition, current therapies are not specifically directed toward basic mechanisms of muscle cell repair and regeneration.
Accordingly, there exists a need for methods and compositions that can induce muscle repair and regeneration speedily and effectively.